Many organizations, including commercial on-line information services and corporate networks, maintain directories of users that can be accessed by other users. In a corporate network, a user may access the directory by looking up a name or an extension number; and in a directory for a commercial service, a user may use a name or a name with other information to obtain records.
Some organizations provide databases from which information can be obtained through publicly accessible web sites. Access is typically made by connecting to the web site and making a request at an input screen. Often the databases have only a small number of records to be retrieved, and in some cases, performance is poor.